Study On The Phase Diagrams Of Co-Pb-Sb And On The Cystal Structures Of A New Compound Ag₅Dy₇Sb

Phase relations in the Co-Pb-Sb ternary system at 500K have been investigated in this work. Moreover, the crystall structures of Ag₅Dy₇Sb have also been studied. The main contents were as follows:1 , The isothermal section of Co-Pb-Sb ternary system at 500KThe phase relationship in the Co-Pb-Sb ternary system at 500k has been studied mainly by means of X-ray powder diffraction with the aid of differential thermal analysis and optical microscope. There are four three-phase regions, nine two-phase regions and six single-phase regions in this ternary system at 500k. No ternary compounds were found. The 6 single-phase regions are: α (Co), β (CoSb), γ (CoSb₂), δ (CoSb₃), ε (Sb), ζ (Pb). The 11 two-phase regions are: α + β, β + γ, γ + δ, δ + ε, ε + ζ, α + ζ , β + ζ , γ + ζ, δ + C . The 4 three-phase regions are: α+β + ζ, β + γ + ζ, γ + δ + ζ, δ + ε + ζ .The maximum solid solubility of Sb in Pb is about 3.3at % Sb determined by the varying of the lattice parameters along with the vanishment of phase.2, Crystal structure of the new compound Ag₅Dy₇SbThe crystal structure of the new compound Ag₅Dy₇Sb has been studied by X-ray powder diffraction technique and refined by Rietveld profile fitting method. The compound has a tetragonal space group P4/nbm(No.125) with the lattice parameters a=0.62201(4)nm, c=0.88134(5)nm, Z=1. D_calc.=8.837g/cm³ and structure type. The Rietveld refinement result was R_p=11. 4% and...